Converting “MPR121 keyboard” sensor filter data into capacitance value?

Using Arduino Microcontrollers
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The project that I'm working on, the MPR121 capacitive touch sensing keyboard connected with a 8051 microcontroller, my first intention when I started implementing the project was to measure the capacitance on the touched electrode, reading the datasheet I learned that I can get the capacitance value from the filter data later on I figured that the value I'm getting from filter data is reverse proportional with the capacitance

Image below shows the relation between capacitance and the voltage

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Image below shows the value range 0-1024 that we can get from the filter data and shows that the value is inverse proportional with the capacitance enter image description here

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I've configured 0x5c and 0x5d register so that charge current I is 16 mikroA and the charge time T is 0.5 mikroS, I'm getting values of filter data in range from 0-600 does this mean that the capacitance is calculated as below..

C=(IT)/V=(160.5)/(0-1024) ?

Thank you!

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What do you need the capacitance value for? Are we sending engineering data to the space shuttle? What is your end goal? Are you trying to identify the user by their showering frequency or perhaps their nervousness? That data might notbe really what you are after. Im plating with the same board right now to make a drum controller.
What are you trying to do with the touch sensors? Dont be so complicated. There is a reason its called the Art of Electronics ..

Jc

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Aren't we suppose to help rather then asking why we need something, does that make any change?

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